Efficacy of Guided Tissue Regeneration Membrane in the Healing of Apicomarginal Defects - A Prospective, Controlled Clinical Trial.

Title: Efficacy of guided tissue regeneration membrane in the healing of apicomarginal defects - A prospective, controlled clinical trial.

Apicomarginal defects, localized bony defects characterised by total deficiency of alveolar bone over the entire root length, have been reported to have lower success rate ranging from 27-37% (1-2). It is proposed that formation of long junctional epithelium during healing phase over the dehisced root surface may contribute to relatively lower success rate of such lesions (1, 3-4).

Successful treatment may, thus, depend not only on elimination of bacteria from the root canal system but also on preventing epithelial proliferation along denuded root surface. GTRtechniques with barrier membranes have been proposed as important adjunct in the management of endodontic-periodontal lesions. Such a membrane, when placed over a bony defect, may prevent the downgrowth of epithelial cells and provide an opportunity for the cells of the periodontal ligament and endosteum to regenerate the lost tissue (5-6).

Literature is replete with case reports and clinical studies (7-18) which demonstrate high success with GTR membrane, and advocate its use in apicomarginal defects (19-20). However, caution must be exercised in drawing any clinically relevant conclusions as none of these clinical studies had a control group. To the best of the investigator knowledge, only three experimental studies (21-23) have evaluated the utility of guided tissue regeneration in apicomarginal defects. While two of these have advocated use of the membrane in such lesions, one could not find any significant benefit of GTR.

Kim et al (24), in a recent prospective clinical study, reported 73.7% healing success by using calcium sulphate and collatape (resorbable collagen membrane) in periapical lesion with complete denudement of buccal bone plate (type F) and 63.6% success even if no membrane is used in E type of lesions. Recently, Song et al (25) also reported 70.4% healing success in apicomarginal defects without use of any GTR technique.These data suggest that there is possibility of healing of apicomarginal defects without use of any GTR technique, by using modern microsurgical techniques.